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Comment by dthul | Hacker News Reader

I don't quite follow. You always have to somehow handle the case the file does not load successfully. In exception languages that handling might be implicit (raise an exception and crash your program) and in "errors as values" languages you at least have to acknowledge that it could go wrong with something like `image.unwrap()` (which turns it into a program aborting panic).

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One of my personal favorite examples of exception handling was a small GUI app with a single top-level exception handler at the event loop that displayed an error message and continued.

That application was extremely robust. You try and save a file and 100 different things could go wrong (network drive unavailable, file is read-only, etc) but it nicely recovered and you could see what the problem was, correct it, and re-save. One single exception handler for the whole app.

> You always have to somehow handle the case the file does not load successfully. In exception languages that handling might be implicit

I.e. you don't have to handle it.

Until you're polishing the program for a stable release, that is.

Right, in both approaches you can choose to handle the error by ignoring it and crashing. In "errors as values" languages you have to make that choice explicit by marking the line with `unwrap`. Saying that this requirement is "the single most unproductive mis-feature a language could have" is extreme hyperbole, no? Adding `unwrap`s during development to imitate implicit exceptions for fast prototyping takes no time or thought at all.

On the contrary, when you later want to polish your program for release these explicit markings make it very easy to find the points in your code where errors can occur and which you don't properly handle yet.

Okay, if there's a simple way to mark some code as "compile this even if it's wrong", it's only a minor annoyance.

But the commenter I responded to seemed to me to be wishing for a language that explicitly disallows that. Maybe I misunderstood?

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